A rotary manipulation type input device of magnetic system is used for selecting and setting operations of various items displayed on a screen such as character inputs in an electronic apparatus.
Such conventional rotary manipulation type input device is explained below while referring to FIG. 4 and FIG. 5.
FIG. 4 is a sectional view of rotary manipulation type input device of magnetic system in a prior art, and FIG. 5 shows a rotary manipulation click-feeling generating mechanism which is one of the essential parts thereof. In FIG. 4 and FIG. 5, a substrate 101 is a flat plate, which is located in the bottom of the rotary manipulation type input device. A box-shaped case 102 opened downward is coupled above the substrate 101.
A dent 101A is formed in the middle of the top of the substrate 101, and a penetration hole 102A is provided in the top of the case 102 located at its opposite position.
A rotary member 103 is composed by fixing a lower columnar shaft 103A, an upper columnar operation shaft 103B, and a disk 103C. The disk 103C is positioned between the columnar shaft 103A and operation shaft 103B. The disk 103C has a magnet which is not shown. In order that the disk 103C is positioned within an internal space formed by the substrate 101 and case 102, the columnar shaft 103A is rotatably fitted into the dent 101A of the substrate 101. The operation shaft 103B is assembled in a state projecting outward from the penetration hole 102A of the case 102.
Near the periphery of the disk 103C, a detecting element 104 such as MR element capable of detecting intensity changes of magnetic field is disposed, and its terminal 104A projects outward by way of the substrate 101.
An elastic spring 105 is fixed on the top of the disk 103C so as to rotate together with the rotary member 103. A protruding contact portion 105A disposed on the elastic spring 105 elastically contacts with undulations 106 formed regularly at the lower side of the top of the case 102.
The conventional magnetic rotary manipulation type input device is composed in such manner. When the rotary member 103 is rotated by turning the operation shaft 103B projecting outward, the magnet of the disk 103C is turned together to change the distribution state of the magnetic field. Fluctuations of the magnetic field intensity are read by the detecting element 104, and a specified signal is sent out from the terminal 104A.
At this time of rotary manipulation, the elastic spring 105 elastically slides on the undulations 106 in a direction indicated by arrow 107 in FIG. 5, and thereby produces a click-feeling.
This click-feeling is transmitted to the user as a sense of rotary manipulation at the time of rotation.
This elastic spring 105 also functions as rotation preventive mechanism to prevent issue of wrong signal due to unexpected rotation of the rotary member 103 in an ordinary state not manipulated by rotation. In the ordinary state, the contact portion 105A is stopped so as to press the side portion of the dents of the undulations 106 by a specified elastic force.
In such conventional magnetic rotary manipulation type input device, however, while the click-feeling is generated at the time of rotary manipulation by combining the elastic spring 105 formed by bending process and the undulations 106 of the case 102, intensity changes of the magnetic field due to move of the magnet attached to the rotary member 103 are detected by the detecting element 104 so as to obtain the amount of rotation of the rotary member 103 or the like. It was hence difficult to synchronize between the rotary click-feeling and signal output.
Or by repeating rotary manipulation, the undulations 106 of the case 102 are worn, and deterioration of rotary click-feeling is likely to occur.